1. Field of the Invention
The present invention relates to a device for correcting injector characteristics, and more particularly, to a technology capable of improving a deviation compensation response speed by performing a deviation correction function on a driving semiconductor while operating an injector for injecting fuel.
2. Description of the Prior Art
As technology has progressed, engines within vehicles have started to receive data from various sensors of the engine when fuel is supplied to the engine during combustion. In particular, an engine control unit (ECU) determines the amount of supplied fuel based on data and which injector is going to inject determined amount of fuel.
Fuel injectors that inject fuel into the combustion chamber are typically disposed in or around each specific combustion chamber in order to effectively provide the appropriate amount of fuel to the chamber upon demand.
In a common rail system, (i.e., one type of fuel injection system), fuel is supplied to a rail from a high-pressure pump. In this type of system, an ECU controls the pressure of the rail based on data received from a pressure sensor which measures the pressure of the rail and outputs a fuel injection signal so that the fuel is appropriately injected.
In the common rail system, an accelerometer is mounted at the center of an engine block and signals generated by the accelerometer are acquired every hour so that the amount of pilot fuel is adjusted to appropriately configure the state of the injector. Even though this is a relatively small amount of injection, it should be managed within a target deviation even if the fuel is repeatedly injected from the same injector, so that the injector can continue to function as designed, and thus the target deviation is a very important factor in managing appropriately the amount of fuel in pilot injection or post injection.
Further, new enhanced exhaust gas regulation have required vehicle manufacturers to focus their attentions on developing a technology which will achieve more environmentally friendly engines. For example, some governments have further restricted Exhaust gas regulation by requiring a further reduction in the number of exhausted fine particles. The most important technology for reducing the number of exhausted fine particles is multi injection. Multi injection is a method of injecting a small amount of fuel into an engine several times at target fuel injection timings, unlike injecting a large amount of fuel into an engine all at once. This makes it possible to reduce the number of exhausted fine particles in comparison to injecting a large amount of fuel all at once.
The key to multi injection method technology is to inject a small amount of fuel accurately into an engine for a short time in comparison to the existing methods, in which it is required to precisely control the injector that injects the fuel.
FIG. 1, for example, illustrates the relationship between the fuel injection amount and injection time of a common injector. Referring to FIG. 1, it can be seen in the common injector, as the fuel injection time decreases, the relationship between the fuel injection amount and the fuel injection time shows nonlinearity. With the nonlinearity of the relationship between the fuel injection amount and the fuel injection time, it is difficult to accurately estimate or control the amount of fuel that is applied during this time period. Accordingly, it is necessary to develop a technology that can compensate for the nonlinearity allowing for more accurate and effective control.